My 5 year old chicken was fine playing in the grass with the others & then a couple hours later stopped walking and cross crossing on top of her feet

[Silveradobug]

My 5 year old chicken was fine playing in the grass with the others & then a couple hours later stopped walking and when she does she’s criss crossing on top of her feet out of balance. I need help. I have to place on the roosting shelf in the evening, and I give her water. In the morning I pick her up and put her in the run. I feed her separately from the others. She is laying down most of the day, if she stands she falls or she has to use her wings to get to another spot.
Any ideas? Anyone else have this happen to them?
She looks beautiful, everything else she’s great. Vet doesn’t know what is wrong

 

[MysteryChicken]

Pictures, & or video please?

 

[Eggcessive]

Have you added any new birds to the flock in recent months? Do you have a rooster who might have hurt her while trying to mate her? How high are the roosts? And what is her diet? Has she laid eggs recently? I had a 3 year old hen, vaccinated for Mareks who for about 5 weeks, lost her balance and sounded similar to your hen. I placed her on the floor in a nest box in the coop. I fed her twice a day, a mixture of wet and dry chicken feed, scrambled egg, a few bits of tuna or canned cat food, and gave Poultry NutriDrench 2 ml daily. She recovered and began walking again, but wouldn’t have unless I had fed and watered her. Make sure that she can reach food and water. You can try a chicken sling chair if she will tolerate it for periods throughout the day with food and water in front of her. Here in the first 2 pages are good ideas for chicken slings:
https://www.backyardchickens.com/threads/versions-of-chick-chairs-please.1166308/